Danebury is an Iron Age hillfort in Hampshire, England, about 19 kilometres (12 mi) north-west of Winchester. The site, covering 5 hectares, was excavated by Barry Cunliffe in the 1970s. Danebury is considered a type-site for hill forts, and was important in developing the understanding of hillforts, as very few others have been so intensively excavated.

A hillfort is a type of fortified refuge or defended settlement located to exploit a rise in elevation for defensive advantage. They are typical of the late European Bronze Age and Iron Age. Some were used in the post-Roman period. The fortification usually follows the contours of a hill and consists of one or more lines of earthworks or stone ramparts, with stockades or defensive walls, and external ditches. If enemies were approaching, the civilians would spot them from a distance.